Actuating mechanism



OCt. 10, 1939. A R Q HOYT 2,176,008

ACTUATING MEGHNIS vFiled. June 25, 1957 wvcwbov HUBERT D. Han/T Patented oet. io, 1939 y Y 2,176,008

UNITED STATES PATENT OFFICE ACTUATING MECHANISM Robert O. Hoyt, Jackson, Mich., assignor to The Tomkins-Johnson Company, Jackson, Mich., a corporation of Michigan Application June 25, 1937, Serial No. 150,357

4 Claims. (Cl. 121-38) This invention relates to riveting machines and bridging member 24. Communicating with one more particularly to an actuating mechanism side of the central part of the cylinder 20 is a therefor. compressed air inletI conduit 25. Communicat- In the copending application of Harold A. Toming With the op-posite side of the cylinder 20 are 5 kins, Serial No. 53,404, filed December 7, 1935, Compressed air outlet conduits 26 and 2'1 which 5 there is disclosed a riveting machine having in turn communicate with the ports 5 and 4, feeding mechanism actuated by a piston movable respectively. in a cylinder by compressed air. In said applica- On the cylindrical portions 23 are disposed tion there is provided a manual control for movesuperficial grooves 28 and 29- for providing a ment of the piston in one direction and an autocommunication between the outlet conduits 28 10 matic control for movement of the piston in the and 21 and the exhaust ports 30 and 3| in the opposite direction. The automatic control comdistributing valve 2|, the exhaust ports 30 and 3| prises an air release button which has not proved extending from the interior of the cylinder 23 to be entirely satisfactory. The present invento the atmosphere. Thus, as the piston 22 is tion comprises a diierent automatic control in reciprocated within the cylinder 20 compressed 15 which moving parts are eliminated and which air from the inlet conduit 25 is directed to either e is more efficient than the one formerly used. the outlet conduit 26 or the Ioutlet conduit 2'I Accordingly an object of the invention is to by the space between the cylindrical portions 23. provide an actuating mechanism having an auto- At the same time compressed air is exhausted matic control. from the outlet conduit 26 or 2'I not'receiving 20 Another object of the invention is to provide compressed air, through one of the supercial an actuating piston and piston rod, the piston grooves 28 or 29 and outlet port 30 or 3|. As disrod having porting for controlling the movement closed in the drawing, compressed air is flowing of the piston. from the inlet conduit through the outlet con- 25 These and other'objects will be apparent from duit 26 to the port 5 and the left end of the cyl- 25 the following speciiication When taken with the inder 2. At the same time the right end of the accompanying drawing, in which v cylinder 2 is being exhausted through the port Fig. 1 is a vertical section `disclosing the inven- 4, the conduit 2'I, superficial groove 29 and the tion, and outlet port 3|. 30 Fig. 2 is a section on the line II-II of Fig. 1 The cylindrical portions 23 of the piston 22 30 disclosing details of the distributing valve. have leakage ports 32 providing communication Referring particularly to the drawing the refbetween the respective ends of the cylinder 2|) erence character I indicates a riveting machine of the distributing valve 2| and the space beon which is mounted one end of acylinder 2. The tween the cylindrical portions 23. Thus, when 35 opposite end of the cylinder 2 is provided with one of the ends of the cylinder 20 is opened to 35 a closing plate 3 having a port 4 communicating the atmosphere and the pressure therein ex- With one end of the interior of the cylinder 2. hausted the piston 22 will be moved to that end A port 5 communicates with the other end of the by the compressed air in the other end and will Cylinder 2. Disposed Within the Cylinder 2 iS a direct compressed air from the inlet conduit 25 PiSiOIl 5 IJIOVided With Suitable packing rings to the corresponding outlet conduit 26 or 2l. 40 1, connected rigidly to a piston rod 8 which The right end of the cylinder 2t is connected extends through a' Stuffing box. 9 in the riveting by a conduit 33 to a push button valve 34 of any machine l' The stumng box 9 1S Compounf hav' standard construction arranged to exhaust to ing an inner portion Il) and an outer portlon II, the atmosphere through the port, 35 upon preseach portion being provided with suitable pack- Sure being exerted upon the spring Stressed but 45 ing' The portion-S 'u and H are Separated by an ton 36. It will be obvious that upon release of annular enclosed space I2. Communicating the pressure on the button 36 the valve 34 w1ll with the annular space I2 1s a conduit I3 which move to Closed position. e Opposite end of w n nd f th 1in sfnccgngglavg e2 L on., Wucge gg the cylinder 20 is exhausted through the conduit Served that the annular Space |2 and the com I3. In order to keep the piston 22 from rotating 0 duit I3 are Sealed Off by the piston rod 3 with respect to the body of the distributing valve Within the cylinder 20 of the distributing valve 2| y the bOdY iS DIOVided With. a bore 45 in which 2| is disposed a piston 22 having spaced substanis press tted or otherwise suitably Secured a Din tially cylindrical portions 23 connected bya 46 which has the inner end thereof disposed 1n 55 a groove 4T in the surface of the bridging member 24.

The particular structure for exhausting through the conduit I3 comprises a U-shaped port 40 in the piston rod 8. The port 40 is formed by drilling centrally in from the right end of the piston rod 8, plugging up the outer end of the bore thus provided, and drilling radially from the surface of the piston rod 8 spaced bores communicating with the central bore. The radial bores of the port 40 are spaced sufficiently to provide a communication between the annular spacing I2 communicating with the conduit I3 and the atmosphere, at the end of the stuing box 9 as shown in dotted lines.

The piston rod 8 is connected to an actuating member 4I which in the present case actuates the rivet positioning member as disclosed in the aforesaid application of Harold A. Tomkins,

, Serial No. 53,404. In operation should it be desired to position a rivet the push button 38 of the valve 34 is manually pressed, it being understood that the valve 34 may be disposed at any convenient place about the machine. Air from the right end of the cylinder 28 of the distributing valve 2i is then exhausted and the piston 22 moves to the right directing compressed air from the conduit 25 through the conduit 2l and the port d at the right end of the cylinder 2. The piston 6 and piston rod 8, together with the actuating member 4| are then forced to the left, the left end of the cylinder 2 being exhausted through the port 5, the conduit 28, the superficial groove 28 and the exhaust port 30. When the piston rod 8 has reached the limit of its stroke to the left the bore i8 provides a communication from the atmosphere through the annular space l2 and the conduit i3 to the left end of the cylinder 28. The compressed air which has leaked through the leakage valve 32 to the left end of the cylinder 28 is then exhausted through said communication to the atmosphere, the piston 23 moves tc the left end of the cylinder 2D and compressed air from the inlet conduit 25 is directed through the outlet conduit 2B and the port 5 to the left end of the cylinder 2 to return the piston and the piston rod 8 and the actuating member 4| to their starting position. It will be, thus, seen that the movement of the actuating inember 4l, in one direction, is brought about by a manual control and its movement in the opposite direction is by an automatic control.

In the aforesaid application of Harold A. Tomkins, Serial No. 53,404, the actuating member actuated a push button valve similar to the push button exhausting valve disclosed herein, to exhaust the left end oi the distributing valve to return the main piston to its starting position. It will be seen that the present structure reduces the number of moving parts and provides a structure which is more simple and more positive in operation. It will, of course, be clear that the invention is not limited to riveting machines but may have other uses. Also other equivalent forms of ports may be substituted for the port 48. Should it be desirable to operate the distributing valve 2l directly by compressed air rather than by exhausting compressed air or to operate an exhausting valve by compressed air, an air supply conduit could be built into the stuing box 9 for connection to the conduit i3 by the port 40, An example of a distributing valve operated by compressed air is disclosed in the copending application of Harold A. Tomkins et al., Serial No. 86,106, iled June 19, 1936 and issued as Patent No. 2,132,811 on October 1l, 1938. As there is no clear line between the piston rod 8 and the actuating member 4l, and there need not be one, the expression operating member has been used in the claims to designate both the actuating member l and the piston rod 8.

Having thus described my invention what I desire to secure by Letters Patent and claim is:

1. A device of the character described comprising, an operating member including a piston rod, a piston for moving the same, a cylinder in which said piston is slidable, a compound stuing box at one end of said cylinder through which said piston rod is slidable, the compound stuffing box comprising two spaced portions and means enclosing the space between said portions, means responsive to the release of pressure to control the movement of operating iuid with respect to said cylinder and piston to move said piston in one direction or the other, a pressure releasing conduit communicating with said iirst named means, the outer end of said conduit communicating with the space in said stuffing box, said space being sealed by said piston rod, and port means in said piston rod for providing communication between said pressure releasing conduit and the atmosphere when said piston is at one end of said cylinder to actuate said means to control the movement of the operating iuid to move said piston to the other end of said cylinder, said port means comprising a longitudinal passage in said piston rod and spaced substantially radially extending ports in said piston rod communicating with said longitudinal passage.

2. A device of the character described comprising, an operating member including a piston rod, a piston for moving the same, a cylinder in which said piston is slidable, a stuiiing box through which said piston rod passes, means rcsponsive to the release of fluid pressure to control the movement of operating fluid with respect to said cylinder and piston to move said piston in one direction or the other, a pressure releasing conduit communicating with said means and having the free end thereof adjacent said box and sealed by said piston rod, at least a portion of said stuffing box being disposed between the free end of said pressure releasing conduit and of said piston, and a port in said piston rod to provide communication between the iree end of said conduit and the atmosphere when said piston is in one end of said cylinder to release pressure to actuate said means to control the movement of the operating uid to move said piston to the other end of said cylinder, said port being U-shaped, one leg of said U being in alignment with said pressure releasing conduit, and the other leg of said U communicating with the atmosphere when said port is in pressure releasing position.

3. A device of the character described comprising an operating member including a piston rod, a piston for moving the same, a cylinder in which said piston is slidable, a compound stuning box at one end of said cylinder through which said piston rod is slidable, the compound stuing box comprising two spaced portions and means enclosing the space between said portions, means responsive to the release of pressure to control the movement of operating uid with respect to said cylinder and piston to move said piston in one direction or the other, a pressure releasing conduit communicating with said first named means, the outer end of said conduit communicating with they space in said stung box, said space being sealed by said piston rod, and port means in said piston rod. for providing communication between said pressure releasing conduit and the atmosphere when said piston is at one end of said cylinder to actuate said means to control the movement of the operating uid to move said piston to the other end of said cylinder, said port means comprising a longitudinal passage in said piston rod, and spaced substantially radially extending ports in said piston rod communicating with said longitudinal passage, one of said radially extending ports communieating with said space and the other of said radially extending ports being opened to the atmosphere when said port is in pressure releasing position.

box in said passage, a port in said head communif eating with said passage, and port means in said piston rod for providing a communication between said rst named port and the atmosphere, said port means Comprising a longitudinal passage in said piston rod with spaced substantially radially extending ports in said piston rod communicating with said longitudinal passage, said port means bridging at least a portion of said stuing box.

ROBERT O. HOYT. 

